This invention relates to hardwood products and particularly but not only to strand lumber and board products formed from eucalypts.
A number of man made timber products are known including particle board (PB), medium density fibreboard (MDF), plywood, laminated veneer lumber (LVL) and oriented strand board (OSB).
Particle board lacks sufficient strength for most structural uses. Plywoods require veneer sheets from relatively high grade logs. MDF products have a number of uses but generally lack structural strength and moisture resistance. OSB and LVL products have a broad range of uses but also suffer from a relatively low resistance to moisture. Their structural strength and holding capacity for fastenings is also directional.
LVL is an adaptation of old technology from the plywood industry and is similarly reliant on old or larger diameter trees, typically 40 years old or more, and around 500 mm in diameter. This provides a relatively low conversion rate from log to LVL product.
Laminated strand lumber (LSL) is another man made timber product but is based on softwoods such as aspen and yellow poplar. These species grow relatively rapidly and this product has also found commercial use as a construction lumber.